My musical idol Frank Zappa wrote a song about this subject. He said, more or less, play dumb and shut up about the MENSA stuff.
Find her finer, sneak up behind her
Wrapped like a mummy till you finally unwind her
Find her blinder, see who designed her
Act like a dummy till you finally grind her
If you should see a girl on the street
Now maybe you might think she is sweet
But if you wanna tickle her treat
Now really, what should you do?
Don't never let her know you are smart
The universe is no place to start
You gotta play it straight from the heart
Or she gonna renunciate you
(That's why you gotta...)
Find her finer, sneak up behind her
Wrapped like a mummy till you finally unwind her
Find her blinder, see who designed her
Act like a dummy till you finally grind her